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Publication numberUS4027905 A
Publication typeGrant
Application numberUS 05/613,018
Publication dateJun 7, 1977
Filing dateSep 12, 1975
Priority dateSep 16, 1974
Publication number05613018, 613018, US 4027905 A, US 4027905A, US-A-4027905, US4027905 A, US4027905A
InventorsToshiaki Shimogawa, Masayuki Morita, Takashi Kawaharazaki
Original AssigneeNippon Soken, Inc.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Seat belt system for vehicle
US 4027905 A
Abstract
A seat belt system for vehicle wherein one end of a seat belt for restraining an occupant is firmly engaged with one end of a steel strip which is held and guided by an anchor member firmly attached to a vehicle body in such a way that when the impact energy acts upon the seat belt, thereby forcing the steel strip out of the anchor member, the strip may be subjected to plastic deformation at least at two positions, whereby the impact energy may be converted into the forces for bending the steel strip as the latter being pulled out of the anchor member. Thus, the impact energy acting on the occupant during a collision may be effectively and safely absorbed.
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Claims(5)
What is claimed is:
1. A vehicle seat belt system, comprising:
a seat belt for restraining an occupant;
a seat belt anchor firmly secured to a vehicle body, said anchor having means providing a series of transversally extending, longitudinally spaced members having respective gaps between adjacent members in the series; and
a variable effect shock absorber comprising a strip of metal woven through said gaps, said strip having a head end secured to one end of the seat belt downstream from said gaps and a tail end protruding upstream of said gaps; means providing a stop on said strip for cooperating with the anchor upon achievement of a predetermined amount of longitudinal advance of the strip;
the transverse cross-sectional area and stiffness of the strip being such that the strip must progressively bend and overcome friction in order to advance through the gaps and accordingly a sustained pulling force is needed to cause said predetermined amount of longitudinal advance;
the cross-sectional area of the strip decreasing from a larger value nearer the head end to a smaller value nearer the tail end, in a manner such that as the strip is pulled to longitudinally advance the strip said predetermined amount, at first the resistance offered to strip advancement is larger and then, as the smaller value transverse cross-sectional area traverses the gaps, the resistance offered to strip advancement decreases, in order to first provide maximum restraint during the initial part of a vehicle accident and to then provide some relaxation.
2. A vehicle seat belt system as set forth in claim 1 wherein
said seat belt is of the three point type having a lap belt, and a shoulder belt,
said anchor member is firmly attached to the upper portion of the vehicle body, and
said one end of said strip is firmly engaged with one end of said shoulder belt.
3. A vehicle seat belt system as set forth in claim 1 wherein
said anchor is in the form of a plate provided with a plurality of transverse slits spaced from each other by a suitable distance so that said strip may be inserted through said slits to provide a zig-zag form.
4. A vehicle seat belt system as set forth in claim 1, wherein said metal strip means is overlaid at a portion on the side of said one end thereof with an additional metal strip, thereby increasing the cross sectional area thereof at said portion.
5. A vehicle seat belt system as set forth in claim 1, wherein said metal strip means has a larger width at a portion on the side of said one end thereof than at the remaining portion thereof, thereby increasing the cross sectional area thereof at said former portion.
Description
BACKGROUND OF THE INVENTION

The present invention relates to a safety seat belt system for use in a vehicle, especially in an automotive vehicle, which system may effectively and safely absorb the impact energy during a collision or the like.

There has been devised and demonstrated an impact energy absorbing device for use with a seat belt system wherein the impact energy acting upon a seat belt due to the sudden acceleration of an occupant during a collision or the like is converted into the force for bending a U-shaped steel strip. However, the greater frictional resistance is generated between the U-shaped strip and a case to which is firmly attached one end of the strip when the strip is bent so that the critical load can not be fixed. As a result, the desired impact energy absorbing characteristics cannot be attained. Furthermore since the U-shaped steel strip and the case are formed integral, in determining a set load limit not only the force for bending the U-shaped strip but also the force for shearing the U-shaped strip away from the case must be taken into consideration. Thus, the conventional energy absorbing device is not satisfactory in practice. Moreover, its energy absorbing efficiency is unsatisfactory. To improve the efficiency, the steel strip must have a greater thickness and width, thus resulting in the increase in the size of the shock absorbing device. Therefore, it becomes impossible to install the energy absorbing device in the space above the shoulder of an occupant.

SUMMARY OF THE INVENTION

One of the objects of the present invention is to provide a vehicle seat belt system which has a higher impact energy absorbing efficiency than any of the conventional seat belt systems.

A further object of the present invention is to provide a vehicle seat belt system which is compact in size yet capable of attaining the desired energy absorbing characteristics.

Briefly stated, to the above and other objects, the present invention provides a vehicle seat belt system comprising a seat belt for restraining an occupant, a metal strip having one end thereof firmly engaged with one end of said seat belt, an anchor member firmly attached to a vehicle body for holding and guiding said strip in such a way that when said strip is forced to be pulled out by the impact exerted to the seal belt, the strip may be subjected to bending at least at two positions.

The above and other objects, features and advantages of the present invention will become more apparent from the following description of illustrative embodiments thereof taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a top view of a first embodiment of the present invention;

FIG. 2 is a sectional view taken along the line II--II of FIG. 1;

FIG. 3 is a perspective view showing the first embodiment installed in an automotive vehicle;

FIG. 4 is a sectional view of the first embodiment used for explanation of the mode of operation thereof;

FIG. 5 is a sectional view of a second embodiment of the present invention;

FIG. 6 is a top view of a third embodiment of the present invention;

FIG. 7 is a sectional view taken along the line VII--VII of FIG. 6;

FIG. 8 is a perspective view of a fourth embodiment of the present invention, the walls of a case being partly broken away;

FIG. 9 is a top view of one of the U-shaped srips used in the fourth embodiment;

FIGS. 10 and 11 are views used for explanation of the mode of operation of the fourth embodiment; and

FIG. 12 is a sectional view of a fifth embodiment of the present invention.

Same reference numerals are used to designate similar parts throughout the figures.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment, FIGS. 1-4

Referring to FIGS. 1 and 2, reference numeral 1 denotes an anchor firmly fixed to a vehicle body; 2, a steel strip; 3 a seat belt having one end portion thereof fitted through an opening formed at one end portion of the steel strip 2, folded back by 180 and sewn itself as best shown in FIG. 2; and 4, transverse shafts disposed in parallel with each other and spaced apart from each other between the side walls of the anchor 1 at right angles with respect to the longitudinal axis thereof, thereby defining slits 4' between them. The steel strip 2 is extended through these slits 4' and partly wrapped around the shafts 4 in the zig-zag form as best shown in FIG. 2.

As shown in FIG. 3, the energy absorbing device with the above construction has its anchor 1 firmly attached with a bolt (not shown) and a nut 5 to the upper portion of the vehicle body 6 for instance, the roof as shown in FIG. 3, and is used for a seat belt system which further comprises a lap belt 7, an inner belt 8, a tongue plate 9, and a belt coiler including a mechanism for locking the seat belt system in case of a collision or the like.

Next referring further to FIG. 4, the mode of operation will be described. When the vehicle collides so that the impact or acceleration is exerted to an occupant, the seat belt is locked to restrain the occupant so that the occupant restraining force; that is, the impact energy for preventing the movement of the occupant acts upon the seat belt 3. The impact energy forces the seat belt 3 to draw the steel strip 2 out of the anchor 1. That is, when the impact energy exceeds the critical force causing the bending at several positions of the steel strip 2, the latter is bent and drawn out of the anchor 1.

The impact energy exerted to the seat belt 3 therefore will not exceed the bending stresses acting upon the steel strip 2 so that the impact energy may be absorbed. When the forced drawing or pulling of the steel strip 2 is stopped as shown in FIG. 4, only the tension load is exerted thereto. The strength of the steel strip 2 is dependent upon the cross sectional configuration.

Referring back to FIG. 1, the steel strip 2 has a wide portion 2b and a reduced portion 2a. After the wide portion 2b has been drawn out of the anchor 1, the reduced portion 2a is pulled out of the anchor 1 while being bent so that the bending load exerted thereto is reduced. As a result, the occupant restraining force is reduced accordingly. Therefore, the desired shock or impact energy absorbing characteristics may be attained by suitably changing the width of the steel strip 2.

Second Embodiment, FIG. 5

The second embodiment shown in FIG. 5 is substantially similar in construction to the first embodiment except that in order to obtain the desired impact energy characteristics an additional steel strip 2' is laminated over the shock absorbing steel strip 2 and wrapped around the shafts 4 in the zig-zag form. The steel strips 2 and 2' may have the same width.

Third Embodiment, FIGS. 6 and 7

The third embodiment shown in FIGS. 6 and 7 is substantially similar in construction to the first embodiment except the construction of the anchor 1. That is the anchor 1 is in the form of a plate provided with a plurality of slits 4' spaced apart from each other by a suitable distance in the longitudinal direction of the anchor 1. The steel strip 2 is alternately inserted into these slits 4' in the zig-zag form. The third embodiment has the impact absorbing function similar to those of the first and second embodiments, and has a distinct advantage over them in that the construction is simpler; that is, the number of the structural members is less.

Even though the first, second and third embodiments are compact in size, they may very efficiently absorb the impact or shock energy because the steel strip 2 (and the additional steel strip 2' in the second embodiment) is subjected to the bending stresses at many portions.

Fourth Embodiment, FIGS. 8-11

Referring to FIGS. 8 and 9, reference numeral 11 denotes a case which is firmly attached to an automotive vehicle body; and 12, and 13, U-shaped strips one ends of which are firmly attached to the bottom and top plates of the case 1 and the other ends of which are firmly attached to one end of the seat belt 3. The shorter or inner leg portions of the U-shaped strips 12 and 13 are made in contact with each other as best shown in FIG. 8.

In the instant embodiment, the U-shaped strips 12 and 13 are made of steel, and each consists of a wide portion 12a and a reduced portion 12b as shown in FIG. 9. The wide portion 12a may absorb a greater impact energy while the reduced portion 12b absorb a relatively small impact energy so that the desired impact energy absorbing characteristics may be obtained. The same is true for the U-shaped strip 13 which has a wide portion and a reduced portion.

The seat belt 3 has its one end firmly engaged with the other ends of the U-shaped strips 12 and 13 in the manner described in conjunction with the first embodiment, and has its the other end attached to a conventional retractor or anchor (not shown).

Next referring to FIGS. 10 and 11, the mode of operation of the fourth embodiment with the above construction will be described. Under the normal conditions, no force for restraining an occupant is exerted to the seat belt 3 so that the U-shaped strips 12 and 13 are maintained in the shape shown in FIG. 10, but when the occupant restraining force exerted to the seat belt during a collision or the like exceeds the critical bending force of the strips 12 and 13; that is, the force required for bending them, the strips 12 and 13 are bent and forced to be pulled out of the case 11 in the direction indicated by the arrow A. That is, the impact force exerted to the seat belt 3 may be converted into the forces deforming the strips 12 and 13.

At the initial stage of the impact exerted to the seat belt 3, the wide portions of the U-shaped strips 12 and 13 absorb the greater energy as they are bent, and when the reduced portions are bent, they absorb the less energy. Therefore, the desired impact energy absorbing characteristics may be obtained.

When the U-shaped strips 12 and 13 are pulled out to the position as shown in FIG. 11, they will not be pulled out any longer so that the impact energy absorbing function is completed. When the strips 12 and 13 are made of steel, their tensile strength is, in general, greater than the bending strength. Therefore, the cross sectional area of the U-shaped strips 12 and 13 is so selected that they may sufficiently withstand the occupant restraining force exerted to the seat belt 3. Furthermore, the bending force applied to the strips 12 and 13 may be suitably controlled by suitably selecting the radius of curvature of the bent portion. Since there is no frictional resistance between the case 11 and the U-shaped strips 12 and 13, the fabrication of the impact absorbing device may be much facilitated, and the stable shock absorbing characteristics may be ensured.

Fifth Embodiment, FIG. 12

The fifth embodiment shown in FIG. 12 is substantially similar in construction to the fourth embodiment except that the case 11 has a a spacer 11a formed integral therewith and extended toward the seat belt 3 from the inner wall of the casing 11 for spacing the U-shaped strips 12 and 13 from each other in such a way that the radius of curvature of the bent portions of the strips 12 and 13 may be made small. Since the radius of curvature is small, the strips 12 and 13 may absorb the greater shock energy as long as they are forced to be pulled out in contact with the spacer 11a. When the strips 12 and 13 are out of contact with the spacer 11a, the radius of curvature of the bent portions is increased so that they are more easily bent than they are still in contact with the spacer. The fifth embodiment has a distinct advantage over the fourth embodiment in that desired impact energy absorbing characteristic may be obtained with the strips 12 and 13 having the same width over the whole length.

As a modification of the fourth embodiment, the strips 12 and 13 may have the same width over the whole length, and the portions corresponding to the wide portions 12a and 13a of the fourth embodiment may be spot welded at several points to the case 11. Therefore at the initial stage, the impact force may be converted to the force for bending the strips 12 and 13 and the forces for shearing the spot-welded joints. Alternatively, the short leg portions which are made into contact with each other may be joined by suitable means or method so that the additional force may be required for severing them apart.

In both the fourth and fifth embodiments, there is no friction between the U-shaped strips and the case so that the stable energy absorbing characteristics may be obtained. That is, the seat belt 3 is pulled out or extended in such a way that the secondary collision of an occupant may be positively prevented.

As described above, even though the impact energy absorbing device in accordance with the present invention is compact in size, the greater impact energy caused by a collision or the like may be absorbed according to a desired shock absorbing program.

It is to be understood that the devices according to the present invention may be incorporated into the two point seat belt installations with the anchor attached to the lower portion of the vehicle body.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3087584 *Apr 10, 1961Apr 30, 1963Zelm Associates Inc VanLoad limiting shock strut
US3280942 *Jan 25, 1965Oct 25, 1966Ralph MillingtonEnergy absorber-metal bender type
US3446533 *Jul 13, 1967May 27, 1969Robbins Seat Belt CoWire-pulling means for absorbing the kinetic energy of a moving body
US3561819 *Sep 26, 1967Feb 9, 1971Chrysler CorpRestraint apparatus
US3889969 *Feb 16, 1973Jun 17, 1975Nissan MotorLinear tension damping device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4142423 *Dec 6, 1977Mar 6, 1979Nissan Motor Company, LimitedShock absorbing device
US4273361 *Jul 31, 1978Jun 16, 1981Nippon Soken, Inc.Seat belt system for vehicle
US4358136 *Nov 28, 1980Nov 9, 1982Nippon Soken, Inc.Energy absorbing device for use with vehicular seat belt
US4630716 *Jun 3, 1985Dec 23, 1986General Motors CorporationStrip roll forming energy absorbing device
US4854608 *Apr 22, 1988Aug 8, 1989Carl F. Schroth GmbhSafety belt
US4978139 *Dec 19, 1989Dec 18, 1990Mercedes-Benz AgEnergy absorbing device for safety belts of motor vehicles
US5211694 *May 21, 1992May 18, 1993Mazda Motor CorporationSafety apparatus including an air bag and a safety belt supported on a vehicle with a deformable coupling
US5294183 *Feb 14, 1992Mar 15, 1994Britax Romer Kindersicherheit GmbhShock absorber for vehicle seat belt
US5464252 *Feb 15, 1994Nov 7, 1995Honda Giken Kogyo Kabushiki KaishaAnchor device for seat belt
US5468053 *May 4, 1994Nov 21, 1995Reynolds Metals CompanyEnergy absorbing beam construction for use with vehicle seat belt restraining systems
US5487562 *Dec 27, 1994Jan 30, 1996Ford Motor CompanyEnergy absorbing apparatus for a motor vehicle
US5609365 *Dec 11, 1995Mar 11, 1997Ford Motor CompanyEnergy absorbing apparatus for a motor vehicle
US5618006 *Feb 23, 1996Apr 8, 1997Trw Vehicle Safety Systems Inc.Seat belt retractor with energy management
US5664807 *Mar 15, 1996Sep 9, 1997Trw Occupant Restraint Systems GmbhForce limitation in a vehicle occupant restraining system
US5700035 *Dec 14, 1995Dec 23, 1997Trw Occupant Restraint Systems GmbhForce limiter for vehicle safety belt systems
US5971489 *Oct 1, 1998Oct 26, 1999Breed Automotive Technology, Inc.Load limiting device for a seat belt
US6378939 *Sep 25, 2000Apr 30, 2002East/West Industries, Inc.Variable energy attenuating apparatus
US6736427 *Jan 25, 2002May 18, 2004Takata (Europe) Vehicle Safety Technology GmbhSafety belt apparatus
US6962245May 22, 2003Nov 8, 2005Worcester Polytechnic InstituteVariable force energy dissipater and decelerator
US7000488 *Jun 5, 2003Feb 21, 2006Siemens AktiengellschaftForce-sensing unit for measuring a belt tensile force acting on a seatbelt lock
US7007976Jun 5, 2003Mar 7, 2006Siemens AktiengesellschaftSeatbelt lock casing with an integrated force-sensing device
US7128374 *Oct 14, 2003Oct 31, 2006Chris Cintos De Seguranca Ltda.Energy absorbing device with torso displacement limiter
US7396184Sep 8, 2005Jul 8, 2008Energy Absorption Systems, Inc.Crash cushion
US7445181Aug 12, 2005Nov 4, 2008East/West Industries, Inc.Variable energy attenuating apparatus
US7484906Dec 4, 2007Feb 3, 2009Energy Absorption Systems, Inc.Crash cushion
US7758277Jan 21, 2009Jul 20, 2010Energy Absorption Systems, Inc.Crash cushion
US7784874 *Dec 8, 2006Aug 31, 2010Ford Global Technologies, LlcEnergy absorbing seat anchor restraint system for child safety seats
US7819469 *Apr 22, 2008Oct 26, 2010Jankel Armouring Ltd.Explosion induced G-force absorption apparatus
US7950870Mar 19, 2009May 31, 2011Energy Absorption Systems, Inc.Energy absorbing vehicle barrier
US7963562Jul 29, 2009Jun 21, 2011Takata-Petri AgSafety belt system for a motor vehicle
US7996964Jul 29, 2009Aug 16, 2011Takata-Petri AgBuckle device
US8074761Jan 6, 2009Dec 13, 2011Energy Absorption Systems, Inc.Crash attenuator
US8182044 *Jul 15, 2009May 22, 2012Jankel Armouring Ltd.Energy absorption apparatus
US8182169Apr 27, 2011May 22, 2012Energy Absorption Systems, Inc.Energy absorbing vehicle barrier
US8230558Jul 5, 2011Jul 31, 2012Takata AGBuckle device
US8302747Feb 7, 2007Nov 6, 2012Airbus Operations GmbhEnergy absorber for aircraft
US8464825Dec 7, 2011Jun 18, 2013Energy Absorption Systems, Inc.Crash attenuator
US8573372Jan 31, 2007Nov 5, 2013Airbus Operations GmbhForce level control for an energy absorber for aircraft
US8662265 *Feb 8, 2007Mar 4, 2014Airbus Operations GmbhEnergy absorber for aircraft
US20090301832 *Feb 8, 2007Dec 10, 2009Airbus Deutschland GmbhEnergy Absorber for Aircraft
US20110006567 *Jul 15, 2009Jan 13, 2011Mike MullenEnergy absorption apparatus
CN101384833BJan 31, 2007Apr 10, 2013空中客车德国运营有限责任公司Force level control for an energy absorber for aircraft
DE3842791A1 *Dec 20, 1988Jun 28, 1990Daimler Benz AgEnergieabsorbierende daempfungsvorrichtung fuer sicherheitsgurte von kraftfahrzeugen
DE19826305A1 *Jun 12, 1998Dec 24, 1998Trw Vehicle Safety SystemsSeat belt for placing around vehicle occupant
DE19826305C2 *Jun 12, 1998Jun 12, 2003Trw Vehicle Safety SystemsSitzgurtvorspannvorrichtung
EP0718163A1 *Dec 19, 1995Jun 26, 1996TRW Occupant Restraint Systems GmbHForce limiter for vehicle seatbelt systems
EP0734922A1 *Mar 7, 1996Oct 2, 1996TRW Occupant Restraint Systems GmbHForce limitation in an occupant restraint system
EP0909684A2 *Oct 8, 1998Apr 21, 1999Breed Automotive Technology, Inc.Energy absorbing belt anchors for safety belts in vehicles
EP1000822A2 *Mar 7, 1996May 17, 2000TRW Occupant Restraint Systems GmbH & Co. KGForce limitation in an occupant restraint system
WO2001051321A1Jan 12, 2001Jul 19, 2001Autoliv Asp IncAdaptive variable load limited for primary occupant safety restraint
WO2002026524A1 *Sep 25, 2001Apr 4, 2002East West IndVariable energy attenuating apparatus
WO2003102402A2 *May 30, 2003Dec 11, 2003Worcester Polytech InstVariable force energy dissipater and decelerator
WO2007093283A1 *Jan 31, 2007Aug 23, 2007Airbus GmbhForce level control for an energy absorber for aircraft
WO2007093311A1 *Feb 7, 2007Aug 23, 2007Airbus GmbhEnergy absorber for aircraft
Classifications
U.S. Classification297/472, 188/371, 280/805
International ClassificationF16F7/14, B60R22/28, A62B35/04, F16F7/12
Cooperative ClassificationB60R22/28, F16F7/123
European ClassificationB60R22/28, F16F7/12B